Reversible mold board plow



1955 A. B. WILKERSON ET AL 2,714,345

REVERSIBLE MOLD BOARD PLOW Filed April 15, 1953 3 Sheets-Sheet l fllllllli AT'I ORNEYS Aug. 2, 1955 A, B, WILKERSON ET AL 2,714,345

REVERSIBLE MOLD BOARD PLOW Filed April 13, 1953 3 Sheets-$heet 2 7 INVENTOiHS 1! ALB. Wilkerson 13 /V/. .E Schac/zi ATTOR N EYS g- 1955 A. B. WILKERSON ET AL 2,714,345

REVERSIBLE ow BOARD PLOW 3 Sheets-Sheet 5 Filed April 13, 1953 INVENT OHS S E Hz M 0 0 mm w 6 a A am is w, E 5.. M

United States Patent 2,714,345 REVERSIBLE MOLD BOARD PLOW Augustus B. Wilkerson and Martin E. Schacht, Fresno, Calif., assignors to Wilkerson & Nutwell, Inc., Fresno, Calif, a corporation of California Application April 13, 1953, Serial No. 348,214 8 Claims. (Cl. 97-26 This invention relates generally to improvements in a reversible mold board plow; i. e. a plowing implement having opposed sets of plows secured on a longitudinally extending, normally fixed but releasable shaft mounted for part-circle rotation whereby to selectively dispose one or the other set of plows in a depending ground working position, the other set then projecting, upwardly in an out-of-use position.

The sets of plows. are disposed relative to each other so that when in a depending ground working position one set throws from the furrow to the right and the other set throws from the furrow to the left. Thus, by using one set of plows in one line of travel of the tractor, and the other set of plows in the opposite lineof travel of the tractor, the earth is turned from all furrows laterally in the same direction, as is desirable to attain an evenly cultivated field, and to provide like wheel tracking by the tractor in the furrows regardless of the directions of travel.

A major object of the present invention is to provide, in a reversible plow as above, a novel mechanism for automatically laterally offsetting the plow supporting portion of the shaft a predetermined distance in the direction of throw of the set of plows which is in depending ground working position; the purpose of such offsetting being to compensate for the side draft which the working set of plows would otherwise impose on the tractor, with resultant tendency of the same to skew laterally, hindering steering.

Another important object of the present invention is to provide a novel manually actuated mechanism for part-rotating the plow supporting shaft so as to selectively dispose one or the other of the sets of plows in depending ground working position.

An additional object of the invention is to provide a novel releasable stop assembly arranged to latch the plow supporting shaft with one or the other of thesets of plows in said depending ground engaging position; said stop assembly being releasable by the manually actuated mechanism which is employed to part-rotate said shaft, as aforesaid.

It is also an object of the invention to provide a reversible mold board plow which is designed for ready and convenient manufacture, and a plow adapted for connection with a conventional lift-type hitch of a wheeled tractor.

Still another object of the invention is to provide a practical and reliable reversible mold board plow, and one which will be exceedingly effective for the purpose for which it is designed.

These objects are accomplished by means of such struc ture and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings:

Fig. l is a side elevation of the reversible plow showing one set of the plows in depending working position,

Patented Aug. 2, 1955 ice . of the mount shown in Fig. 2.

Fig. 4 is an enlarged fragmentary plan view showing a portion of the manually actuated mechanism employed to part-rotate the plow supporting shaft.

Fig. 5 is an enlarged fragmentary elevation showing the stop assembly.

Referring now more particularly to the characters of reference on the drawings, the implement comprises a heavy-duty, longitudinally extending shaft 1 including at the rear end, in rigid rearwardly projecting relation, an extension sleeve 2 which supports, in. diametrally opposed relation, one set of plows 3 and another set of plows 4; each set comprising two plows in longitudinally spaced relation, and corresponding plows of the sets being fixed to the extension sleeve 2 by parallel, substantially radially projecting cross arms 30:.

When one set of the plows is in depending ground working position, and the other set is in an upwardly projecting, out-of-use position, all of the plows face laterally in the same direction. As a result one set of plows, when working, throws from the furrow to the right, whereas the other set of plows, when working, throws from the furrow to the left. Consequently, when the tractor reverses its line of travel in a field, and the sets of plows are reversed in their positions, the throw from all of the furrows is laterally in the same direction.

The shaft 1, ahead of the sleeve 2, projects through a substantially horizontal mounting frame, indicated generally at 5; said mounting frame 5 being of open con struction and including a rear cross bar 6, transversely spaced side bars 7, andat the front-an upstanding, forwardly facing guideway 8 of rigid, open, rectangular form.

Centrally of its ends the rear cross bar 6 is fitted with a self-alining bearing 9 through which the shaft 1 projects, thence extending lengthwise of the mounting frame 5 and passing through another self-alining bearing 10 carried in a laterally shiftable slide block 11.

The slide block 11 runs in guided relation top and bottom on horizontal transverse upper and lower guide rails 12 and 13 included in the guideway 8.

The mounting frame 5 has secured thereto at the rear an upstanding A-frarne 14, while at the front another A-frame 15 upstands from the top of the guideway 8. A diagonal brace 16 extends from the upper portion of the rear A-frame 14 at a forward and downward incline to connection with the top of the guideway 8 centrally of its ends.

The mounting frame 5 is fitted on opposite sides, and at the rear, with projecting trunnions 17 adapted to be pivotally connected with the rear ends of the transversely spaced lift arms 18 of a lift-type hitch on the rear of a tractor (not shown) whose rear wheels are indicated at 19.

The tractor hitch also includes a centrally disposed top link 20 which extends rearwardly through the front A- frame 15 to pivotal connection, as at 21, with the upper end of the rear A-frame 14. With such arrangement the implement is supported by the tractor hitch and can be raised or lowered by the latter as desired.

The following manually actuated mechanism is employed to half-circle rotate the shaft 1 in order to reverse the positions of the sets of plows 3 and 4.

The front A-frame 15 is fitted, on top, with a relatively short longitudinal bearing sleeve 22 through which a tubular shaft 23 extends; such tubular shaft being fitted,

at its rear end, with a sprocket 24 which drives an endless chain 25; the latter extending downwardly and turning in driving relation about another sprocket 26 on the shaft 1 within the confines of the mounting frame 5.

At the front end the tubular shaft 23 includes a lateral bracket 27, and a crank 23 is pivoted at its inner end, as at 29, to the bracket 27, thence spanning across the end of shaft 23.

A plunger rod 30, whose purpose will hereinafter appear, is slidably disposed in the tubular shaft 23, and said rod is pivoted-as at 31-at its forward end to the crank 28.

The crank 23 is within reach of theoperator of the tractor, and by manipulating said crank to swing it through an arc of approximately 180, half-circle rotation is imparted to the shaft 1, reversing the positions of the sets of plows 3 and 4.

A U-shaped, vertically adjustable stop 32 is mounted in connection with the front A-frame l5 and overlies the crank, whereby to limit its motion to substantially 180.

The following stop assembly is employed to properly position the shaft 1 with one or the other of the sets of plows in depending. ground working position:

Immediately forwardly of the cross bar 6 the shaft 1 is fitted with a collar 33 having a rigid radial stop finger 34 projecting therefrom; there being upstanding adjustable stop bolts 35 supported by flanges 36 on opposite sides of the shaft 1. One of the stop bolts is engaged by the finger 34 when one set of the plows is in depending ground working position, while said finger rests against the other stop bolt when the other set of plows is in said position. The flanges 36 are fixed to the cross bar 6, and the stop bolts 35 are adjustable so as to accurately position the sets of plows when each assumes the depending ground working position.

In order to prevent any rotation of the shaft 1 when one set or the other of the plows is in use the following arrangement is provided:

A cross shaft 37 extends in intersecting relation below the shaft 1 and ahead of the flanges 36, beingsupported by ears 38' which project from said flanges.

Rearwardly extending, downwardly opening hook bolts 39 arefi-xed in connection with the cross shaft 3 7 in position to normally directly aline with the stop bolts 35, whereby in either position of the stop finger 34 to maintain it against escape from the engaged one of said stop bolts.

It is necessary that the hook bolts 39 be swung to a position, as shown in dotted lines in Fig. 5, when it is desired to rotate the shaft 1 for the purpose of reversing the plows. This is accomplished by providing the shaft 37 with a radial lever arm 44) to which an upstanding link 41 is pivotally connected. At its upper end the link 41- is pivoted to one end of a somewhat bellcrank-like lever 42 pivoted intermediate its ends, as at 43, to a rigid attachment ear 44 on the upper end of the rear A-frame 14. At the end opposite the link 41 the bellcrank-like lever 42 is connected in loose-play relation, as at 45, with the rear end' of the plunger rod 30.

Before the operator swings the crank 23 to reverse the sets of plows he first pulls forwardly on such crank, shifting itfrom the full-line position to the dotted line position as in Fig. 4. This to move forwardly, working the bellcrank-like lever 42 in a direction which thrusts downwardly on the link 41 and lever arm 40, turning the cross shaft 37 in a direction to shift the hook bolts 39 to an out-of-the-way position as in. dotted lines in Fig. 5. Thereafter, the crank 28 can be swung through its 180 arc of travel without the hook bolts 39 interfering with the corresponding motion of the radial stopfinger 34.

The mechanism for automatically laterally offsetting therear or plow supporting portion of the shaft in the direction of throw from the furrow when either of the causes the plunger rod 30 sets of plows is in depending ground working position comprises, in combination with the self-alining bearings 9 and 10, and the laterally shiftable slide block 11, the following:

Forwardly of the slide block 11 the shaft 1 is fitted with a vertical face plate 46 to which is secured a laterally adjustable attachment plate 47; the securing means being normally tight bolts 48 extending through slots 49 to clamp the plates 46 and 47 together.

A stub shaft 50' projects forwardly from the attachment plate 47 on the longitudinal center line of the implement but laterally eccentric to the axis of shaft 1; such eccentricity being predetermined by adjustment of said plate 47. p

The stub shaft 50 is connected by a swivel bearing 51 to a connecting rod 52 which projects laterally, as shown.

At its outer end the connecting rod 52 is connected by a longitudinal axis bearing 53' to a boss 54 which projects horizontally forward from one side of the guideway 8';

Withthe above arrangement the stub shaft 50" is al-' ways maintained on said longitudinal center line of the implement.

By reason of the eccentric connection of the rod 52 to the shaft 1, such shaftupon half-circle rotation to certain distance to the left relative to the longitudinal center line of theimplement; such offsetting being accompanied by a corresponding lateral shifting of the slide block 11 in the guideway 8. When this occurs, and because bearing 9 cannot move laterally, the rear end portion of the shaft 1 is offset laterally to the right, being the direction in which the mentioned set of plows is throwing from the furrow.

Conversely, when the-shaft 1 is half-circle rotated sothat the set of plows which throws to the left is in depending ground workingposition, the ecc'entricstub shaft 50' causes lateral offsetting of the forward end of shaft I to the right relative to said longitudinal center line, with resultant lateral offsetting to the left of the rear or plow supporting portion of said' shaft; i. e. in the same direction that the then depending set of plows is throwin'g' flOIi'l'thQ furrow.

With such automatiolateral offsetting of the rear portion of the shaft 1 to*right or leftwhen the corresponding set' of plowsiswo'rking, such offsetting effectively compensates for theside draft which the plows would otherwise impose on the" tractor, and which would tend to'caus'e lateral skewing of the tractor and impair proper steeringthereo'fr The lateral offsetting of the rear portion of theshaft 1' is therefore an important feature, and

- .one which contributes substantially to the proper and effective functioning of the implement.

From the foregoing description it will be readily seen that there has been produced such a device as substantiah ly fulfills the objects of the invention, as set forth herein.

While this specification sets forth in detail the present andpreferred construction ofthe device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described the invention, the following is claimed as new and useful, and upon which Letters Patent are desired:

1. A reversible plow implement comprising a mounting frame adapted to be supported for movement along the ground, a longitudinal shaft, journal means securing the shaft on the mounting frame, the shaft projecting rearwardly of said frame, said journal means supporting the shaft for lateral offsetting at the rear to right or left relative to the longitudinal center line of the implement, opposed plow structures secured to and projecting from the shaft rearwardly of the frame, means to part-circle rotate the shaft to selectively dispose either plow struc ture in depending ground working position with the other plow structure then projecting upwardly in an outof-use position, and means to cause said lateral offsetting of the rear of the shaft in the direction of throw from the furrow of the plow structure in said depending; ground working position; said journal means including a self-alining bearing on the frame supporting the shaft intermediate its ends, and said last named means including a lateral connection between the frame and shaft in longitudinally spaced relation to said bearing, ant. said connection being coupled to the shaft in laterally eccentric relation to the axis of the latter.

2. A reversible plow implement comprising a mounting frame adapted to be supported for movement along the ground, a longitudinal shaft, journal means securing the shaft on the mounting frame, the shaft projecting rear-. wardly of said frame, said journal means supporting the shaft for lateral offsetting at the rear to right or left relative to the longitudinal center line of the implement,

opposed plow structures secured to and projecting from the shaft rearwardly of the frame, means to part-circle rotate the shaft to selectively dispose either plow structure in depending ground working position with the other plow structure then projecting upwardly in an out-of-use position, and means to cause said lateral oifsetting of the rear of the shaft in the direction of throw from the furrow of the plow structure in said depending ground working position; said journal means including longitudinally spaced self-alining bearings on the shaft, the rear bearing being fixed on the frame against lateral displacement and the front bearing being laterally shiftably supported on the frame; and said shaft offsetting means embodying a longitudinal stub shaft secured in connection with and projecting from the front end of the journaled shaft in laterally ofiset relation to its axis, and a lateral connecting rod pivotally connected between the stub shaft and frame.

3. A reversible plow implement comprising a mounting frame adapted to be supported for travel along the ground, longitudinally spaced self-alining bearings on the frame, the rear bearing being fixed against lateral displacement, a slide unit attaching the front bearing to the frame for lateral shifting motion, a longitudinal shaft journaled in said bearings and projecting rearwardly from the frame, opposed plow structures secured to and projecting from the shaft rearwardly of said frame, actuating means mounted on the frame and connected to the shaft to part-circle rotate said shaft so as to selectively dispose either plow structure in depending ground Working position with the other plow structure then projecting upwardly in an out-of-use position, and a lateral connecting rod pivoted at one end to the frame and at the other end to the front end of the shaft in laterally eccentric relation to the axis of the latter.

4. A reversible plow implement, as in claim 3, includ ing a laterally adjustable plate secured to the front end of the shaft; said plate having a longitudinal stub shaft projecting therefrom in said eccentric relation to the axis of the journaled shaft, and the adjacent end of the connecting rod being pivoted on said stub shaft.

5. A reversible plow implement comprising a mounting frame adapted to be supported for movement along the ground, a longitudinal shaft journaled on the frame and projecting rearwardly thereof, substantially radially opposed plow structures secured to the rearwardly projecting portion of the shaft, actuating means mounted on the frame and connected to the shaft to part-circle rotate said shaft so as to selectively dispose either plow structure in depending ground working position with the other plow structure then projecting upwardly in an out-of-use position, a stop finger projecting from the shaft, stop elements on the frame disposed for engagement by said finger when corresponding plow structures are in said depending ground Working position, and releasable latch means operative to normally prevent escape of said finger from the engaged stop element.

6. A reversible plow implement, as in claim 5, in which said stop elements are disposed on opposite sides of the shaft, and said latch means comprising a transverse shaft journaled in the frame, hooks on said transverse shaft with the outer end portions of the hooks normally adjacent and alined with corresponding stop elements, the finger normally lying between one stop element and the related hook, and means connected to the transverse shaft and operable by the shaft rotating means to rotate the transverse shaft in a direction to swing the hooks clear of said stop elements and the rotative path of movement of said finger.

7. A reversible plow implement comprising a substantially horizontal mounting frame adapted for connection to a lift-type hitch of a tractor having an operators seat adjacent the rear, a longitudinal shaft journaled on and projecting rearwardly from the mounting frame, substantially radially opposed plow structures secured to the rearwardly projecting portion of the shaft, an upstanding frame on the mounting frame, a longitudinal actuating shaft journaled on the upstanding frame, said actuating shaft being tubular, a plunger rod slidable in the tubular actuating shaft, a hand crank pivoted intermediate its ends to the front of the plunger rod and pivoted at the inner end to the tubular shaft in laterally offset relation, the crank being accessible to the tractor operator from the seat and operative to both slide the rod and rotate the tubular actuating shaft, driving connections between the tubular actuating shaft and plow structure supporting shaft, stop and releasable latch means arranged to maintain the plow structure supporting shaft against rotation when either of said plow structures is in said dependent ground working position, and means responsive to sliding of the plunger rod operative to release said latch means.

8. A reversible plow implement comprising a mounting frame adapted to be supported for travel along the ground, a longitudinal shaft, opposed plows secured to and projecting from the shaft rearwardly of the frame, self-alining bearings disposed adjacent the ends of the frame and in which the shaft is journaled one bearing being secured on the frame at one end thereof, means mounting the other bearing on the other end of the frame for lateral shifting movement so as to enable the shaft to be disposed at an angle to the right or left of the longitudinal center line of the implement, actuating means mounted on the frame and connected to the frame to part-circle rotate said shaft so as to selectively dispose one plow in a depending ground working position when the other plow projects upwardly in an inoperative position, and a lateral connecting rod pivoted at one end to said bearing mounting means in laterally eccentric relation to the axis of the shaft and at the other end to the frame.

References Cited in the file of this patent UNITED STATES PATENTS 120,572 Chapman Nov. 7, 1371 1,358,158 Karn Nov. 9, 1920 1,410,917 Hee Mar. 28, 1922 2,625,090 Pursche Jan. 13, 1953 2,644,385 Brown July 7, 1953 FOREIGN PATENTS 629,302 France July 19, 1927 552,302 Germany June 10, 1932 455,658 Great Britain Oct. 26, 1936 665,663 Great Britain Jan. 30, 1952 665,666 Great Britain Jan. 30, 1952 430,587 Italy Feb. 16, 1948 

